You didn't ask if people bring charges base on their own beliefs, you asked if the police should believe someone base on that person's words and nothing else. Two very different things. The police and definitely the jury should consider more than eyewitness testimonies, even from the allege victim him/herself.Currently police bring charges against someone based only on the word of a single victim all the time. Those of you who argue they don't, are just inaccurate. To do anything else ignores the realities of how and where crimes are committed. It's up to the jury if they believe the witness by the high standard of proof of beyond a reasonable doubt.